Apparatus for pressure bonding two or more frame members in the forming of frame corners

ABSTRACT

For pressure bonding the joint between two angularly related frame members, a pair of clamps, disposed, one against each side of said frame members and spanning the joint involved, said clamps being interconnected by bolts through the frame members to either side of the joint whereby pressure may be applied at the joint following the application of glue to the joint ends of said frame members. A wedge frame member may be included between the first mentioned frame members and the two joints thus formed may likewise be pressure bonded.

United States Patent Inventor Erwin Dimter 7918 Rudolf-Diesel-Strassel2, lllertissen, Germany Appl. No. 2,748 Filed Jan. 14. 1970 PatentedSept. 7, 1971 Priority Jan. 28, 1969 Germany P 19 03 945.3

APPARATUS FOR PRESSURE BONDING TWO OR MORE FRAME MEMBERS IN THE FORMINGOF FRAME CORNERS 7 Claims, 8 Drawing Figs.

US. Cl 100/93, 156/583, 269/47, 269/112, 144/3 Int. Cl ..B02c 11/08,B30b 15/34 Field of Search 100/93;

[56] References Cited UNITED STATES PATENTS 994,630 6/191 1 Bergstrom269/49 1,500,824 7/1924 Kline 269/47 X 1,795,525 3/1931 Trautner 269/472,186,198 1/1940 Krumbach 269/47 2,804,893 9/1957 Carper .1 269/47 X2,820,495 1/1958 Wetzler 100/93 Primary Examiner- Peter FeldmanAllorney- Edward Brosler ABSTRACT: For pressure bonding the jointbetween two angularly related frame members, a pair of clamps, disposed,one against each side of said frame members and spanning the jointinvolved, said clamps being interconnected by bolts through the framemembers to either side of the joint whereby pressure may be applied atthe joint following the application of glue to the joint ends of saidframe members. A wedge frame member may be included between the firstmentioned frame members and the two joints thus formed may likewise bepressure bonded.

PATENTEDSEP 1m 3,603,246

- sum 1 or 3 muunn l N V E N TO R HiM/vp/Mnm Attorney PATENTEDSEP H97!3.503245 sum 2 BF 3 l NVENTOR 1 EEW/N D/MTER Attorney APPARATUS FORPRESSURE BONDING TWO OR MORE FRAME MEMBERS IN THEFORMING OF FRAME fCORNERS The present invention relates to an apparatus for the pressconnecting of two or more wooden work pieces provided at their abuttingsides with wedge-shaped tenons to form frame corners. I

lt is already known to make frame corners from bent oblongwooden-pieces. For this on the one hand only woods of comparativelysmall cross section could be used and on the other hand it was notpossible to bend such wooden pieces to form angular frame corners. It isalso already known to cut through obliquely rectangular boards and toconnect the two wooden workpieces thus resulting; by gluing to formangular frame corners.

According to this method several wooden workpieces could be connected toone another to form a multiangular frame corner.

With this method the two abutting sides of the wooden workpieces formingbetween themselves the gluing joint were provided with glue and 'thenpressed against one another. These frame corners could however not besubjected to any great stresses in the plane of the glued joint as onlythe holding force of the glue was decisive for the tensile strength andthe abutting faces glued to one another were comparatively small. Forincreasing the tensile strength one then went over to providing theabutting faces with wedge-shaped tenons then depositing on these, glueand then pressing the tenoned abutting faces against one another.

in the latter method there then'arose difficulties when constructionalparts of large cross section had to be assembled to form supportingconstructional parts. With large cross sections pressures of about60,000 kg. are necessary in order to obtain a somewhat satisfactoryconnection. Toapply such a force in a controlled manner failed with theconventional devices due to the fact that they were not transportableand necessitated such a space requirement which was frequently notavailable at the building sitellt has already been proposed to insert onboth sides of the glued joints, holes in the wooden workpieces, then toinsert rods into these holes and then by means of a set of pulleys drawthe rods together. On the one hand this method was complicated, timeconsuming and very expensive and on the other hand in doing so a uniformpressure could not be attained on all holes so that the holes weredeformed to become partly oval. This known apparatus could not berealized economically.

The object of the present invention is to provide an apparatus of theabove-mentioned kind which can easily be cmploycd at building siteswithout large space requirements and produces a uniform high pressurecorresponding to the requirements.

The apparatus according to the invention proposed for the solution ofthis problem is characterized by two pairs of bolts lying parallel andat the same distance from one another which engage through bores inwhich less stressed zones of the wooden workpieces to be connected toone another are provided and at their ends carry pressure transmittingmembers connected to one another in pairs contacting from top to bottomon the wooden workpieces with cross pieces connecting extension of theflat irons. By means ofthese oblong holes the pressures medium cylindersmay undergo a rough adjustment so that the piston stroke uponcompression of the glued joint, is adequate.

The apparatus according to the invention is thus composed of severalsimple individual parts whichaccording to their airrangement represent apositive connection whereby via the pressure medium cylinder anaccurately adjustable uniform pressure can be produced. The number ofdevices used may be as desired corresponding to the width of the woodenworkpieces to be connected to oneanother. As a rule however at least twodevices are used in order to ensure an accurate pres sure distribution.Instead of the pressure. medium cylinders spindles may be employed whichhowever is less adover the glued joint which is heated by resistance'heating bands. Thus the glue joint is hardened in one totwo minuteswhich ensures the full load-capacity of the constructionalp'art y afterthe complete hardening. The high'frequen'cy energy u'sed i I hithertofor such purposes is not only uneconomic but cannot be used for reasonsof the steel press parts present.

the pressure transmitting members on one wooden workpiece to oneanother, engage the piston rods of pressure medium cylinders which aremounted by means of crosspieces in holes of flat irons which aresuspended on nose pieces of the pressure transmitting members lying onthe other wooden workpiece. Thus it is of advantage for all parts of theapparatus lying above and below the wooden workpieces to be connected tobe formed as mirror images. As pressure medium cylinders, hydrauliccylinders known per as may be provided which are fed from a common pump.

It is also advantageous for the holes provided in the flat irons for thebearing of the crosspieces of the pressure medium cylinders to be formedas oblong holes in the longitudinal The cross pieces of the pressuremedium cylinders may furthermore be supported according to the inventionby means of slide shoes on the wooden workpieces which ensures asatisfactory guiding of-the pressure medium cylinders opposite thewooden workpieces.

With the arrangement according to the invention bulky constructionalparts may be composed of several wooden workpieces economically at thebuilding site to form frame corners.

The apparatus may of course also be employed where wooden workpieceshave to be connected in a longitudinal expansion to one another on thebuilding site.

The invention will be described in more detail with reference to theaccompanying drawings which shows several optional embodiments:

FIG. 1 shows a curved frame corner;

FIG. 2 shows a frame corner composed of two wooden workpieces;

FIG. 3 shows a frame corner composed of three wooden workpieces;

FIG. 4 shows a view from above of two wooden workpieces to be connectedto one another using three devices;

FIG. 5 shows a view like FIG. 4 wherein thrce wooden workpieces areconnected to one another by means of two devices;

FIG. 6 shows on an enlarged scale compared with H65. 4 and 5 a device inside view;

FIG. 7 shows a view from above according to FIG. 6 with use ofresistance heating bands;

FIG. 8 shows a press device including resistance heating bands. FIG. 1shows a known frame corner made by bonding the wooden workpiece l. Theframe corner likewise known according to FIG. 2 consists of the twowooden workpieces 2 and 3 between the abutting faces of which a gluejoint 5 is located. The frame corner according to FIG. 3 consists of thetwo outer wooden pieces 2 and 3 as well as an inserted wooden workpiece4. Thus two glue joints 6' and 7 result.

The construction of the device according to the invention is explainedin more detail with reference to the FIGS. 6-to 8 in which two woodenpieces 2 and 3 r are connected to one another. The abutting faces of thewooden workpieces 2 and 3 are provided with wedge-shaped tenons 39 and40 and from the glue joint 5. In the less stressed zones of the woodenworkpieces 2 and 3 are disposed bores 12 which lie parallel to oneanother and evenly spaced. For the making of. the bores, templets knownper se may be used. Through the bores 12, bolts 8, 9, and 11 areinserted and on their ends 8a and 8b to 1 1a and 11b projecting on bothsides from the bores 12 are fixed pressure transmitting members 13 to20. On the pressure transmittingmembers 13, 14, 15 and 16 which contactthe wooden work piece 2 are disposed nose pieces 30 to 33 on the flatirons 34 in which oblong holes are formed. In the opposite end of theflat irons 34 are provided further holes 29 formed as oblong holes inwhich engage nose pieces 42 of cross pieces 21 and 22 of pressure mediumcylinders 25 and 26. The piston rods 23 and 24 of the pressure medium 25and 26 press against the cross pieces 27 and 28 which connect thepressure transmitting members 17 and 19 and 18 and to one another.

The pressure medium cylinders and 26 are suitably supplied with pressureoil which is supplied via a common pump to provide a uniform pressure onall sides. I

As can be seen in FIG. 8 in order to obtain a more rapid bonding of theglue, a steel band 36 with resistance heating bands 27 is placed aroundthe glue joint 5 which resistance heating bands are connected to atransformer via pole clamps.

The crosspieces 21 and 22 of the pressure medium cylinders 25 and 26 maybe formed on the side adjacent the wooden workpiece as a sliding shoe38.

According to the embodiment in accordance with FIG, 4 two woodenworkpieces 2 and 3 are provided with three devices according to theinvention.

In the embodiment according to FIG. 5 the two wooden workpieces 2 and 3are connected to one another with the insertion in between of a furtherwooden workpiece 4 using two devices. Thus there is provided in thecentral area of the wooden workpiece 4 a bore 43 into which a bolt 35 isinserted which is supported against the flat iron 34 when pressingtogether the three wooden workpieces 2, 4 and 3; the force componentsindicated by the arrows 44 and 45 cause a displacement of the woodenworkpiece 4 upwards (in the plane ofthe drawing).

What 1 claim is:

17 An apparatus for the press connecting of two or more woodenworkpieces provided on their abutting sides with wedge-shaped tenons toform frame corners. characterized by two pairs of bolts (8, 9. 18, ll)lying parallel and evenly spaced apart which engage through bores (18)provided in the carry pressure transmitting members (13-20) connected toone another in pairs contacting from top to bottorh on the woodenworkpieces (2, 3) and on crosspieces (21, 22) which connect togetherpressure transmitting members (17, 19) and (18, 20) on one woodenworkpiece (3), and engage the piston rods (23, 24) of pressure mediumcylinders (25, 26) which are mounted by means of crosspieces (27, 28) inholes (29) of flat irons (34) suspended on nosepieces (30-33) of thepressure transmitting members (13, 15 and 14, 16) in contact with theother wooden workpiece (2).

2. An apparatus according to claim 1, characterized in that all parts ofthe apparatus lying above and under the wooden workpieces to beconnected are formed as mirror images.

3. An apparatus according to claim 1, characterized in that as pressuremedium cylinders (25, 26) hydraulic cylinders known per se are providedwhich are supplied from a common 4. An apparatus according to claim 1,characterized in that the holes (29) provided in that flat irons (34)for the bearing to the cross pieces (27, 28) of the pressure mediumcylinders (25, 26 are formed as oblong holes lying in the longitudinalextension of the flat irons.

5. An apparatus according to claim 1, characterized in that theapparatus for the press connecting of two wooden work I pieces (2, 3)with the insertion ofa further wooden workpiece (4) with an additionalbolt engages through a bore (43) p of the wooden workpiece (4) insertedthere between whereby the bolt (35) is sup orted against the outside ofthese flat irons (34) which lie on t e side of the apparatus lyingopposite the 7 force components (arrows 44, 45) occurring with thepressing

1. An apparatus for the press connecting of two or more woodenworkpieces provided on their abutting sides with wedge-shaped tenons toform frame corners, characterized by two pairs of bolts (8, 9, 18, 11)lying parallel and evenly spaced apart which engage through bores (18)provided in the less stressed zones of the wooden workpieces (2, 3) tobe connected to one another and at their ends (8a-11a and 8b-11a) carrypressure transmitting members (13-20) connected to one another in pairscontacting from top to bottom on the wooden workpieces (2, 3) and oncrosspieces (21, 22) which connect together pressure transmittingmembers (17, 19) and (18, 20) on one wooden workpiece (3), and engagethe piston rods (23, 24) of pressure medium cylinders (25, 26) which aremounted by means of crosspiecEs (27, 28) in holes (29) of flat irons(34) suspended on nosepieces (30-33) of the pressure transmittingmembers (13, 15 and 14, 16) in contact with the other wooden workpiece(2).
 2. An apparatus according to claim 1, characterized in that allparts of the apparatus lying above and under the wooden workpieces to beconnected are formed as mirror images.
 3. An apparatus according toclaim 1, characterized in that as pressure medium cylinders (25, 26)hydraulic cylinders known per se are provided which are supplied from acommon pump.
 4. An apparatus according to claim 1, characterized in thatthe holes (29) provided in that flat irons (34) for the bearing to thecross pieces (27, 28) of the pressure medium cylinders (25, 26) areformed as oblong holes lying in the longitudinal extension of the flatirons.
 5. An apparatus according to claim 1, characterized in that theapparatus for the press connecting of two wooden workpieces (2, 3) withthe insertion of a further wooden workpiece (4) with an additional bolt(35) engages through a bore (43) of the wooden workpiece (4) insertedthere between whereby the bolt (35) is supported against the outside ofthese flat irons (34) which lie on the side of the apparatus lyingopposite the force components (arrows 44, 45) occurring with thepressing operation.
 6. An apparatus according to claim 1, characterizedin that over the glue joint (5) a steel band (36) is disposed which isheated by resistance heating bands (37).
 7. An apparatus according toclaim 1, characterized in that the crosspieces (23, 24) of the pressuremedium cylinders (25, 26) are supported on the wooden workpieces (2, 3)by means of sliding shoes (38).